GCC emits a warning: progs/test_tcpbpf_kern.c:60:9: error: ‘op’ is used uninitialized [-Werror=uninitialized] when an uninialized op is used iwth a "+r" constraint. The + modifier means a read-write operand, but that operand in the selftest is just written to. This patch changes the selftest to use a "=r" constraint. This pacifies GCC. Tested in bpf-next master. No regressions. Signed-off-by: Jose E. Marchesi <jose.marchesi@xxxxxxxxxx> Cc: Yonghong Song <yhs@xxxxxxxx> Cc: Eduard Zingerman <eddyz87@xxxxxxxxx> Cc: david.faust@xxxxxxxxxx Cc: cupertino.miranda@xxxxxxxxxx --- tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c index cf7ed8cbb1fe..a3f3f43fc195 100644 --- a/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c +++ b/tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c @@ -59,7 +59,7 @@ int bpf_testcb(struct bpf_sock_ops *skops) asm volatile ( "%[op] = *(u32 *)(%[skops] +96)" - : [op] "+r"(op) + : [op] "=r"(op) : [skops] "r"(skops) :); -- 2.30.2